1. Field of the Invention
The present invention relates to a pellicle, a producing method thereof and an adhesive, and more particularly, to a pellicle used for a purpose of preventing dusts from attaching to a mask or a reticle (hereinafer referred simply to as mask or the like) used in the photolithography step in a process for producing an integrated circuit, to a process for producing a pellicle, and to an adhesive for pellicles.
2. Description of the Related Art
Based on the demand for rendering the line widths of integrated circuits finer, there is a request of using exposure light sources having extremely short wavelengths. When ultraviolet rays having such short wavelengths are used, the conventional pellicle films, such as cellulose, have severe degradation, and only insufficient durability is attained. Therefore, in recent years, pellicle films made of fluorine-containing polymers are used. However, practical adhesive strength was not attained using epoxy-based adhesives conventionally used for adhering pellicle films on pellicle frames due to the excellent detachabilities of the fluorine-containing polymers. Moreover, epoxy-based adhesives have only insufficient light resistance to the ultraviolet rays having short wavelengths.
In order to solve such problems about the adhesives for pellicle films made of fluorine-containing polymers, a pellicle comprising a pellicle film made of a fluorine-containing organic substance adhered to a pellicle frame with an adhesive made of the same fluorine-containing organic substance has also been proposed (Japanese Patent Application Laid-open No. 6-67409). However, if such a conventional adhesive is used, three-hour air-drying is required after the application of a solution comprising a fluorine-containing organic substance dissolved in an solvent to a frame, and additionally, when a film and an adhesive are adhered together, it is necessary to heat them to a temperature of 100° C. or higher. For this reason, the adhering process takes time and effort. Furthermore, since heat is applied, there is a problem that members, such as a frame, are distorted.